#include<iostream>
using namespace std;
int main()
{
    cout << "Vvedite nomer mesyatsa\t";
    int n;
    cin >> n;
    if (n!= 2 && n < 13 && n > 0)
    {
    if (n % 2)
      cout << 31 << endl;
    else
      cout << 30 << endl;
    return 0;
    }
    else if (n == 2)
    {
    cout << 28 << endl;
    return 0;
    }
    else
    {
    cout << "Neverno vveden nomer\n";
    return 1;
    }
}
